Blood rheology measuring apparatus

ABSTRACT

A blood rheology measuring apparatus has a measuring portion for measuring blood circulation information inside of a living body from outside of the living body. The blood circulation information is a maximum blood flow velocity for one pulse. An information processing portion processes the measured information from the measuring portion to obtain information concerning a blood rheology of the living body.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a blood rheology measuring apparatusindicating a flowability referred to generally as a fluent/viscousdegree of blood, particularly to a technology of measuring an amount ofa blood flow flowing in the artery, discerning a very small circulatingblood flow rate constituting a basis of activity of the human textureand carrying out assessment of health, diagnosis of disease, assessmentof effect of medicine and the like.

2. Description of the Related Art

It has conventionally been carried out to measure blood rheology forcarrying out assessment of health of human being, diagnosis of disease,assessment of effect of medicine on the human body, assessment ofsoundness and functional performance of food or the like, and carryingout the assessment and the diagnosis from a result thereof. As aconventional technology, there is known a method presented by YujiKikuchi under a title of “Measurement of total blood flowability using acapillary model” in a professional magazine “Food research resultinformation, No.11 issued in 1999”, that is, a method of sampling bloodfrom a subject, using a micro-channel array fabricated by a lithographicmethod and measuring blood rheology from a pass time period of bloodunder constant pressure.

According to the method, first, the elbow of the subject is disinfectedby alcohol cotton and blood is sampled from the elbow vein by using avacuum blood sampling tube in which there is put a heparin solution toconstitute a quantity of 5% as an anticoagulant by using a 1 mldisposable syringe and a 23G disposable needle before sampling blood.Next, there are prepared micro-channels of a capillary model fabricatedby a silicon chip (micro-channel array silicon chip), which are alignedin parallel with each other by 8736 pieces with a size of a width of 7μm, a length of 30 μm and a depth of 4.5 μm, subjected to ultrasoniccleaning in a pertinent amount of mixture solution of distilled water,ethanol and a liquid neutral detergent (trade name: mamalemon) (aiming1:1:0.3) and sets to a blood rheology measuring apparatus (MC-FAN).Further, after cleaning a cylinder for a sample in the apparatus bydistilled water, physiological salt water is substituted therefor andmicro-channel array pass time period is measured by a difference of 20cmAq by using 100 μl of the physiological salt water.

After measuring the physiological salt water, blood is measured. First,200 through 300 μl of a blood sample is sampled by using the 1 mldisposable syringe attached with the 23G disposable needle and furtherattached with about 10 cm of a polyethylene tube at a needle tipthereof, a tip of the polyethylene tube is put to the bottom of thecylinder and the blood sample is injected to push up the remainingphysiological salt water. Further, the blood sample is controlled toconstitute 100 μl while extracting blood from an upper end openingportion of the cylinder by using the polyethylene tube and amicro-channel array pass time period of 100 μl of blood is measured by adifference of 20 cmAq. similar to the case of the physiological saltwater.

With regard to the microchannel array pass time periods of thephysiological salt water and the sampled blood calculated in this way,the pass time period of the sampled blood is corrected by the pass timeperiod of the physiological salt water and the time period is defined asa total blood pass time period to constitute an index of blood rheology.For example, when the total blood pass time period is short, bloodrheology is low and therefore, the blood flows in the capillary tubewithout resistance. That is, there is increased the very smallcirculating blood flow amount constituting the basis of activity of thehuman texture and therefore, the total blood pass time period cancertify the healthy body.

However, according to the conventional blood rheology measuring methodusing the micro-channel array, blood needs to sample by piercing theelbow by using the injection needle in order to sample blood from thesubject. Therefore, in carrying out an in-vivo test for examininginfluence of a food component on blood rheology, blood cannot be sampledfrom same person for many times in a day and there poses a problem thata continuous test is difficult. Further, even when an individual intendsto measure blood rheology by sampling blood by oneself at one's ownhouse apart from a medical institution, according to a method of using amicro-channel array as in the conventional example, the apparatus cannotbe put in one's own house, a pertinent treatment cannot be carried outand therefore, there also poses a problem that blood rheology can bemeasured only at a medical institution.

It is an aspect of the present invention to provide a noninvasive bloodrheology measuring apparatus, which is also a small-sized and portableapparatus, capable of simply and conveniently measuring blood rheologyinformation without sampling blood from a subject when measuring bloodrheology and means for enabling to measure blood rheology at any time,at anywhere and simply even at other than a medical institution withoutapplying burden on the subject.

SUMMARY OF THE INVENTION

A blood rheology measuring apparatus according to the invention is onthe basis of a constitution comprising means for noninvasively detectinga flow velocity of the blood flowing in the blood vessel as a Dopplershift signal by transmitting and receiving a wave from a face of theskin and means for analyzing blood rheology from a temporal change of avalue of the flow velocity of the blood detected by the means and theapparatus is small-sized, portable and capable of simply measuring bloodrheology at any time at anywhere even at outside of a medicalinstitution without applying burden on a subject.

Hence, according to an aspect of the invention, there is provided ablood rheology measuring apparatus comprising a measuring portion formeasuring information with regard to blood circulation at inside of aliving body from a surface of the living body, and a signal processingportion for processing a signal detected from the measuring portion,wherein information with regard to a blood rheology is provided as aresult of processing the signal.

Further, the measuring portion and the signal processing portion areintegrally or separately made portable to thereby enable to provide theinformation with regard to the blood rheology continuously or daily.Further, the information with regard to the blood circulation to bemeasured in the measuring portion is a change in a blood flow velocitybased on a Doppler effect by a blood flow. The measuring portion is anultrasonic wave sensor for transmitting and receiving an ultrasonicwave.

Further, the measuring portion is constructed by a constitutionconstituting a sensor for detecting information with regard to a pulsewave or a constitution having an input device for inputting individualinformation of gender or the like of a person to be measured forcorrecting measured data.

As a result of the signal processing, information with regard to lifehabit suitable for the person to be measured is informed to a subjectbased on a result of measuring the blood rheology of the person to bemeasured or there is provided a data holding portion for storinginformation with regard to the measured blood rheology to thereby enableto hold daily blood rheology information of the person to be measured.

Further, the measuring portion is constructed a constitution integratedto a blood pressure meter or a pulse meter and capable of being utilizedin measuring blood pressure or measuring pulse.

Further, there is provided inputting means for inputting daily eatinghabit information of the person to be measured and there is provideddetermining means for determining whether the eating habit of the personto be measured is suitable for the person to be measured from theinformation with regard to the blood rheology to thereby enable toinform a result of determination by the determining means to the personto be measured.

Further, for correcting the information with regard to the measuredblood rheology, there is constructed a constitution having a temperaturemeasuring portion brought into contact with a surface of the living bodyfor measuring temperature of inside or the surface of the living body ata vicinity of the measuring portion or the measuring portion generatesheat in measuring to thereby elevate a temperature of the measuringportion.

Further, the measuring portion is constructed by a constitution held bya holding portion capable of holding the measuring portion by bringingthe measuring portion in to contact with the surface of the living bodyor a constitution in which the measuring portion and the temperaturemeasuring portion are blocked from outside air, or the holding portionis constituted by a member having insulating performance or a memberhaving elasticity such as rubber. Further, a shape of the holdingportion is constituted by a shape of a finger ring or a shape of amouse.

Further, in analyzing the blood rheology from the temporal change of theflow velocity value of the blood, there is constructed (1) aconstitution utilizing a maximum blood flow velocity for one pulse, (2)a constitution dividing the maximum blood flow velocity for one pulse byan integrated value of a pulse velocity, (3) a constitution forproviding a Doppler shift intensity waveform reflected and returned fromblood flow, calculating an intensity of each of frequency components ofthe Doppler shift signal (histogram), extracting a maximum frequency ina signal at an intensity level equal to or larger than a threshold inthe histogram or a maximum frequency when an integrated value from alower frequency component reaches a predetermined rate of a totalthereof in the histogram, providing a waveform of a temporal change ofthe extracted frequency (frequency waveform) and analyzing bloodrheology based on the maximum frequency in the frequency waveform, or(4) a constitution for analyzing blood rheology by an area value of aportion at and above a line connecting a minimum value of a one pulsewaveform and a minimum value of a successive pulse waveform of thefrequency waveform.

Further, the means for noninvasively detecting the flow velocity of theblood flowing in the blood vessel includes a constitution of adopting anultrasonic wave transmitter and receiver for transmitting and receivingan ultrasonic wave to and from the artery of the finger portion, or aconstitution for adopting an ultrasonic wave transmitter and receiverfor transmitting and receiving an ultrasonic wave to and from the arteryat the finger tip portion.

Further, according to another aspect of the invention, there is provideda blood rheology measuring apparatus including a compensating functionby providing (1) means for operating and compensating for an amount of achange in the flow velocity of the blood based on expansion andconstruction of the blood vessel by a temperature value detected bymeans for detecting temperature of the blood vessel portion fordetecting the blood flow and comprising (2) means for operating andcompensating for an amount of a change based on blood pressure bydividing by a blood pressure value detected by blood pressure measuringmeans.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram for explaining a first blood rheology analyzingmethod according to the invention;

FIG. 2 is a diagram showing a Doppler shift intensity waveform of asignal received by an ultrasonic receiver according to the invention;

FIG. 3 is a graph showing a relationship between an FFT number insubjecting the Doppler shift intensity signal to high-velocity Fouriertransformation and a pulse maximum sensitivity;

FIG. 4 is a diagram showing a frequency waveform according to theinvention extracted from the Doppler shift intensity signal;

FIG. 5A is a diagram for explaining a second blood rheology analyzingmethod according to the invention extracted from a frequency waveformand FIG. 5B is a diagram for explaining a third blood rheology analyzingmethod according to the invention;

FIGS. 6A and 6B are explanatory views of Embodiment 1 (Embodiment 2)according to the invention in which FIG. 6A shows a finger ring typeblood rheology measuring apparatus mounted to the finger and FIG. 6Billustrates a section taken along a line A–A′ of FIG. 6A;

FIG. 7 is an explanatory view of Embodiment 1 according to the inventionand is a perspective sectional view of inside of a finger ring viewingfrom a B direction shown in FIG. 6B;

FIG. 8 is a block diagram showing an inner constitution of a signalprocessing portion of a blood rheology measuring apparatus of Embodiment1 (Embodiments 3, 4, 5) and a state of connecting the signal processingportion and an ultrasonic sensor portion at inside of a finger ringportion;

FIG. 9 is an explanatory view of Embodiment 2 according to the inventionand is a perspective sectional view of inside of a finger ring viewingfrom the B direction shown in FIG. 6B;

FIG. 10 is a block diagram showing an inner constitution of a signalprocessing portion of a blood rheology measuring apparatus of Embodiment2 (Embodiments 4, 5, 6) and a state of connecting the signal processingportion, an ultrasonic sensor portion at inside of a finger ring portionand a temperature sensor;

FIG. 11 is a view showing an outlook constitution of a blood rheologymeasuring apparatus constituting Embodiment 3 (Embodiment 4);

FIG. 12 illustrates a section taken along a line A–A′ of FIG. 11 withrespect to Embodiment 3;

FIG. 13 illustrates a section taken along a line B–B′ of FIG. 11 withrespect to Embodiment 3;

FIG. 14 is a view showing a sectional view of a mouse type bloodrheology measuring apparatus of Embodiment 4, illustrating a sectiontaken along a line A–A′ of FIG. 11;

FIG. 15A is an outlook view of a wrist watch type blood rheologymeasuring apparatus constituting a fifth embodiment of the invention andFIG. 5B is a view showing a measuring state of the wrist watch typeblood rheology measuring apparatus;

FIG. 16 illustrates a section taken along a line A–A′ of FIG. 15B of thewrist watch type blood rheology measuring apparatus constituting thefifth embodiment;

FIG. 17 is a constitution view of an outlook of a finger sack type bloodrheology measuring apparatus of a blood rheology measuring apparatusconstituting a sixth embodiment of the invention;

FIG. 18 illustrates a section taken along a line A–A′ of FIG. 17according to the sixth embodiment of the invention;

FIGS. 19A and 19B indicate data of a seventh embodiment of the inventionby graphs;

FIGS. 20A and 20B indicate data of an eighth embodiment of the inventionby graphs;

FIGS. 21A and 21B indicate data of a ninth embodiment of the inventionby graphs;

FIG. 22 illustrates a tenth embodiment of the invention;

FIG. 23 illustrates the tenth embodiment of the invention;

FIG. 24 illustrates an eleventh embodiment of the invention

FIG. 25 illustrates a twelfth embodiment of the invention;

FIG. 26 illustrates a thirteenth embodiment of the invention;

FIG. 27 illustrates a fourteenth embodiment of the invention; and

FIG. 28 illustrates a fifteenth embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The blood rheology, that is, the flowability of blood is brought into aclose relationship with a viscosity of blood and when a change in ablood flow velocity is large, it can be regarded that there is broughtabout a state of low viscosity of blood. According to the conventionalmeasuring method, the viscosity is measured by the time period by whicha predetermined amount of blood passes through the micro-channel arrayby a predetermined water column pressure difference and the time periodis compared with that of the physiological salt water constituting areference, which basically constitutes measurement of the viscosity. Itis deduced that when blood is fluent, the blood is to flow excellentlyat inside of the blood vessel and blood flow is continued even attimings at which delivering pressure is not operated in the pumpingaction of the heart. The measurement principle of the blood rheologymeasuring apparatus according to the invention is based on the knowledgethat there is a correlation between a form of a temporal change of ablood flow velocity appearing in pulsing with rheology of blood forcalculating blood rheology from a change in the blood flow velocityappearing in pulsation.

Further, the blood rheology measuring apparatus of the inventioncomprises means for noninvasively detecting the flow velocity of bloodflowing in the blood vessel as a Doppler shift signal by transmittingand receiving a wave to and from the skin face and means for analyzing ablood rheology from a change over time of a value of the blood flowvelocity detected by the means as its basic constitution. A wave signalhaving a constant frequency radiated from the skin face to inside of thebody, is returned by being reflected by a substance in the body. Byreceiving a reflected wave signal thereof, the flow velocity of bloodflowing in the blood vessel included therein is detected and areflecting substance is not specified to the blood flow in the bloodvessel. In the case of the blood flow in the blood vessel, the bloodflow is moved with a velocity component and therefore, according to areflected wave thereof, a frequency of wave is shifted by the Doppler'seffect, however, in the case of a stationary substance which is notprovided with a velocity component, such as bone or the blood vessel,the wave is reflected and returned to stay with the constant frequency.

Further, there are present not only blood in the blood vessel, to whichattention is paid as a substance having a velocity component but alsovarious substances such as blood or lymph in the capillary directed invarious directions and reflected waves from these are superposed on areceived wave. A component the same as that of the frequency on atransmitting side is reflected from a stationary substance andtherefore, the component can easily be removed. A physical amountintended to detect in the invention is a flow velocity of blood in theblood vessel to which attention is paid and generally a signal havingthe highest level as the frequency component corresponds to an averageflow velocity of flow of blood in the blood vessel and therefore, thecomponent is extracted. In detecting the flow velocity of blood, thetechnology of the conventional ultrasonic blood flow meter is applicableas it is. Further, although ultrasonic wave is generally used for a waveused in detecting the blood flow velocity, other wave of laser or thelike can also be used. Further, a pulse waveform is one of indexesindicating a blood circulating dynamic state and it seems that bymeasuring a rise velocity of the pulse waveform or measuring a velocityof changing a diameter of the blood vessel, a correlation thereof withblood rheology can be obtained.

An explanation will be given of a method of analyzing blood rheologyfrom a temporal change of a blood flow velocity value detected in theinvention as follows. FIG. 1 shows a graph of a temporal change of ablood flow velocity in accordance with pulsing. As a characteristiccomponent of blood rheology, by utilizing a maximum blood flow velocityVx, the inventors have been able to confirm a correlation thereof withblood rheology and have acquired knowledge that even a ratio Vn of Vx ascompared with a pulse velocity waveform, the ratio has a correlationwith blood rheology. The ratio Vn is calculated by dividing the maximumblood flow velocity Vx by an integrated value of the pulse velocitywaveform (an integrated value of the pulse velocity waveform in oneperiod of pulse: a pattern portion in the drawing). This is a firstmethod of analyzing blood rheology according to the invention.Vn=C×Vx/(integrated value of pulse velocity waveform)  (1)where notation C designates a correction coefficient. The apparatus ofthe invention carries out an in-vivo measurement, the measured bloodflow velocity is not only dependent on blood rheology but also dependenton conditions such as thickness and wall quality of the blood vessel andblood pressure and therefore, although the blood flow velocityinformation can relatively measure blood rheology, the blood flowvelocity information cannot absolutely measure blood rheology. Hence, itis necessary as the premise of measurement of the invention to acquire acorrection amount in correspondence with an absolute value by carryingout a correction in parallel with measurement by the conventional methodcapable of carrying out the absolute measurement by comparing with areference of physiological salt water or the like and the method of theinvention. Further, it has been confirmed that even by utilizing themaximum blood flow velocity Vx without carrying out the correction ofEquation (1), there is established the correlation with blood rheology.

Next, an explanation will be given of a second method of analyzing bloodrheology according to the invention. There is arranged an ultrasonicsensor paired with an ultrasonic wave incident portion and an ultrasonicwave detecting portion to be opposed to the artery disposed proximatelyto the surface of the body and an ultrasonic wave is radiated toward theartery by exciting an ultrasonic wave transmitter of the ultrasonic waveincident portion by a constant frequency of about 9.6 MHz. In theultrasonic wave detecting portion, the ultrasonic wave detecting portionreceives an ultrasonic wave signal reflected to return by inside of thebody. As described above, the received signal includes ultrasonic wavesreflected by various portions at inside of the body, when a reflectingsubstance is stationary, a frequency of a reflected wave remainsunchanged from the frequency of the incident wave and when thereflecting substance is a moving substance, the reflected wave isreflected by undergoing a frequency shift (Doppler shift) in accordancewith a moving amount thereof. An intensity of the Doppler shift isextracted from the received signal to acquire a temporal procedurethereof. A waveform diagram of FIG. 2 indicates the temporal procedureand the temporal procedure is referred to as a Doppler shift intensitywaveform. The Doppler shift intensity waveform is measured by using asampling rate equal to or larger than 1/5000 of the frequency of theinput waveform.

Specifically, when the Doppler shift intensity waveform is calculated,in the case of the input waveform frequency of 9.6 MHz, the samplingrate is made to be equal to or larger than 1.92 kHz. The reason is thatwhen the sampling rate is less than 1.92 kHz, the frequency waveformcannot be reproduced from the Doppler shift intensity waveform. In thecase of the input waveform frequency of 9.6 MHz, the Doppler shiftintensity waveform sampled at 1.92 KHz or higher, can measure afrequency component of an intensity change of the Doppler shiftintensity equal to or lower than 0.96 kHz at minimum. When the frequencywaveform is calculated from the frequency component, rheology of aviscous can be calculated. According to the invention, by subjecting theDoppler shift intensity signal to high-speed Fourier transformation(FFT), there is calculated an intensity distribution (histogram) of afrequency indicating the periodicity.

In order to analyze the frequency waveform, there is needed data atevery 250 ms (8 Hz) at the latest. This is a rate when a maximum numberof a pulse number is assumed to be 240 pulses (in correspondence with apulse number in exercise) and normally, a temporal change of thefrequency is analyzed by using data at every 23.22 ms. This is a ratesufficiently fast for 250 ms. Further, a relationship between thesampling rate for calculating the Doppler shift intensity wave form anda number of sampling data used in carrying out FFT, is brought into aclose relationship with a pulse number of a person to be measured, forexample, in considering a case of measuring a person pulsing at 60pulses, when there is used a sampling frequency (1.92 kHz) constitutinga limit capable of reproducing the Doppler intensity waveform, thefrequency waveform in accordance with pulsing cannot be provided unlessthe number of FFT is made to be equal to or less than 1000. Further,when a maximum sensitivity of pulsing is increased to 90 pulses, 120pulses, unless the number of FFT is reduced to 600, 500, the frequencywaveform in accordance with pulsing cannot be provided. FIG. 3 is agraph showing the relationship. It has been confirmed that when thenumber of FFT is made to be about 256, the number is almost maderegardless of increasing pulsation or increasing the sampling rate andtherefore, generally, the number of FFT is made to be about 256.

According to the invention, there are adopted the following two methodsas methods of calculating a frequency waveform from a frequencycomponent. One of the methods is a threshold designating method andother thereof is a rate comparing method. First, with regard to thethreshold designating method, the procedure is as follows.

-   (1) There is carried out FFT of a Doppler shift intensity signal to    calculate a frequency component.-   (2) A power spectrum value of a frequency calculated by FFET is    compared with a certain threshold.-   (3) Frequencies having power spectrum values larger than the    threshold are sampled.-   (4) A highest frequency in the sampled frequencies is selected as a    frequency component for forming the frequency waveform. The highest    frequency indicates a reflected wave from a reflecting substance in    the body having the fastest moving speed and although there is a    case that the reflected wave indicates motion of muscle or the like,    generally, the reflected wave can be interpreted to correspond to a    flow velocity of blood flowing in the artery to which attention is    paid.-   (5) The frequency waveform is formed by repeating operation of    steps (1) through (4) for Doppler shift intensity signals at    respective time points. Here, a temporal resolution of the frequency    waveform is constituted by a product of the sampling rate of the    Doppler shift intensity waveform by the FFT number.

FIG. 4 shows a frequency waveform provided thereby. Generally, thefrequency waveform is formed with 10000 as the threshold. The waveformis similar to the pulse waveform provided from blood flow velocityinformation (refer to FIG. 1).

Next, with regard to another method of calculating the frequencywaveform from one frequency component, or the rate comparing method, theprocedure is as follows.

-   (1) There is carried out FFT of a Doppler shift intensity waveform    for calculating a frequency component.-   (2) There is calculated a total of power spectrum values of    frequencies calculated by FFT.-   (3) The power spectrum values are added successively from power    spectrum values having lower frequencies.-   (4) The sum is divided by the total of the power spectrum values to    thereby calculate a rate.-   (5) The rate is compared with a certain set rate.-   (6) A frequency having a power spectrum value added when the rate    becomes larger than the set rate as a result of comparison, is    selected as a frequency component for forming the frequency    waveform.-   (7) The frequency waveform is formed by repeating operation of    steps (1) through (6) with regard to Doppler shift intensity signals    at respective time points. Here, a temporal resolution of the    frequency waveform is constituted by a product of the sampling rate    of the Doppler shift intensity waveform by the FFT number.

There is provided a frequency waveform similar to that in FIG. 4 by sucha procedure. The method is a method tried in view of the fact that thethreshold designating method is liable to be effected by influence ofhigh frequency noise and a high frequency region is abandoned to removethe high frequency noise. There is not an absolute significance in therate set value in this case, generally, the frequency waveform is formedwith 80% (0.8) as the rate set value. The frequency waveform by themethod is difficult to be effected by influence of high frequency noise,on the other hand, the method is inferior to the threshold designatingmethod in view of accuracy and therefore, the threshold designatingmethod may be adopted by dealing with the high frequency noise bypreventing unrealistic high frequency components from being picked up.

In the case of a second method of analyzing blood rheology according tothe invention, as shown by FIG. 5A, a maximum frequency is specified inthe provided frequency waveform and rheology is calculated by using themaximum frequency. The method is based on a prediction that when bloodis fluent, blood flow is easy to flow and the maximum blood flowvelocity is increased. Although generally, there is calculated anaverage of maximum frequency values of about three pulses, as shown byFIG. 4, there is a case in which the frequency waveform includes lowfrequency components and maximum frequencies at respective pulses vary.When the maximum frequency is shifted at respective pulse, sampling maybe carried out at a long period of pulsing.

In the case of a third method of analyzing blood rheology according tothe invention, a pulse waveform of one pulse is sampled from a frequencywaveform and an area value thereof is calculated to thereby calculaterheology. The method is based on a prediction that when blood is fluent,even at timings at which delivery pressure by pumping action of theheart is not applied, blood is predicted to flow as it is by inertiaforce and therefore, an integrated value of one pulse will be increased.However, it is predicted that information at low flow velocity near to 0includes not few other velocity information of the vein or the like andtherefore, according to the invention, as shown by FIG. 5B, there iscalculated an area of a portion at and above a line connecting a minimumvalue of a waveform of one pulse and a minimum value of a waveform ofsuccessive pulse.

Measurement of blood rheology according to the invention is based oninformation of blood flow at inside of the actual blood vessel in thebody and therefore, the detected blood flow signal is varied by beingeffected with influence of expansion or contraction of the blood vesselbased on body temperature or influence of blood pressure. That is, whenthe body temperature rises, the blood vessel is expanded to be thick,blood becomes easy to flow, blood flow velocity is increased, however,this is a factor irrelevant to blood rheology. Further, a variation inthe blood pressure value corresponds to a change in pump pressureoperated to a flow path and the flow velocity (blood flow velocity) isvaried in accordance therewith. This is also a variation in blood flowbased on a factor irrelevant to blood rheology. Hence, according to theinvention, there is adopted a constitution in which these values areseparately detected and amounts of variation based thereon arecompensated for.

(Embodiment 1)

An explanation will be given of a blood rheology measuring apparatusaccording to an embodiment of the invention in reference to the attacheddrawings. The apparatus is constituted by the first blood rheologyanalyzing method according to the invention of calculating the ratio bydividing the maximum blood flow velocity Vx shown in FIG. 1 by anintegrated value of a pulse velocity waveform (an integrated value of apulse velocity waveform in one period of pulse). FIGS. 6A and 6B areviews showing an outlook constitution of the embodiment of the bloodrheology measuring apparatus used in the embodiment. As shown by FIG.6A, the blood rheology measuring apparatus is constituted by beingclassified in two of a finger ring portion 1 and a signal processingportion 2. FIG. 6B illustrates a section taken along a line A–A′ of FIG.6A with regard to Embodiment 1. As shown by FIG. 6B, an ultrasonic wavesensor portion 3 is present on an inner side of the finger ring portion1. FIG. 7 shows a sectional view of inside of the finger ring viewedfrom a B direction shown in FIG. 6B. In the ultrasonic sensor portion 3,an ultrasonic wave incident portion 31 and an ultrasonic wave detectingportion 32 are attached at a belly portion of the finger 6. Further, thearteries 5 disposed in the finger 6 are extended to the finger tip bypassing both sides of the belly portion of the finger 6 and therefore,in order to measure flow of blood of the artery, the ultrasonic waveincident portion 31 and the ultrasonic wave detecting portion 32 areattached to a portion of the finger 6 shifted to the left of the centerof the belly as shown by FIG. 6B such that an ultrasonic wave can beincident to aim at the artery. Thereby, reflection from the artery, canfirmly be caught and accuracy of measuring blood flow is promoted.Although the portions 31 and 32 are attached to shift to the left, evenwhen the portions 31 and 32 are attached to shift to the right to aim atthe artery on the right side, the effect stays the same.

The blood rheology measuring apparatus of Embodiment 1 is normallyportable by mounting the finger ring portion 1 on the finger 6 andmounting the signal processing portion 2 on the arm. Further, also thesignal processing portion 2 may be mounted on the finger 6 similar tothe finger ring portion 1. The signal processing portion 2 and theultrasonic wave incident portion 31 and the ultrasonic wave detectingportion 32 installed at the finger ring portion 1, are connected by leadwires, a driving voltage signal is inputted from the signal processingportion 2 to the ultrasonic wave incident portion 31 via the lead wireand at the ultrasonic wave detecting portion 32, a measured voltagesignal is inputted to the signal processing portion 2.

FIG. 8 shows a block diagram showing an inner constitution of the signalprocessing portion 2 of the blood rheology measuring apparatus accordingto Embodiment 1 and a state of connecting the signal processing portion2 and the ultrasonic wave sensor portion 3 at inside of the finger ringportion 1. As illustrated, the signal processing portion 2 is generallyconstituted by a drive portion 21, a receive portion 22, a signaloperating portion 23 and an output portion 24. The drive portion 21 ofEmbodiment 1 oscillates PZT installed at the ultrasonic incident portion31 and transmits drive voltage for making an ultrasonic wave incident onthe artery 5. The receive portion 22 receives voltage generated when PZTinstalled at the ultrasonic wave detecting portion 32 receives theultrasonic wave.

The signal operating portion 23 carries out various processings withregard to measurement of blood rheology by executing processing programsstored to a storage region (illustration is omitted) provided at insidethereof and outputs a result of the processings to the output portion24. Further, the signal operating portion 23 calculates the Dopplereffect of blood flow by comparing a frequency of the ultrasonic waveemitted from the ultrasonic wave incident portion 31 and a frequency ofthe ultrasonic wave received by the ultrasonic wave detecting portion32. Further, the signal operating portion 23 calculates a flow velocityof blood flowing in the artery 6 by a change in the frequency andcalculates a temporal change of the velocity. Further, there is acorrelation between the form of the temporal change of the blood flowvelocity appearing in pulsing and rheology of blood and blood rheologyis calculated from the change of the blood flow velocity appearing inpulsing. For example, when the change of the blood flow is large, it isregarded that there is brought about a state in which the viscosity ofblood is low.

Next, an explanation will be given of the blood rheology measuringmethod of the embodiment. FIG. 1 shows the graph of the temporal changeof the blood flow velocity accompanied by pulsing. As a characteristiccomponent of blood rheology, the maximum blood flow velocity Vx ispointed out. As shown by the following equation, the maximum blood flowvelocity Vx is corrected to be V1 by using a correction coefficient C1.V1=C1×Vx

When the blood rheology measuring method of the invention is applied toa person having blood rheology in which the total blood pass time periodcalculated by using the maximum blood flow velocity Vx and themicro-channel array is 60 sec to thereby calculate the pulse velocitywaveform and the correction coefficient C1 is calculated such that V1becomes 60, in the case in which the total blood pass time period of thesame person is changed to 35 sec, when V1 is calculated from Equation 1by using C1 calculated above, V1 shows a value of 35.

Further, the ratio Vn of the maximum blood flow velocity Vx as comparedwith the pulse velocity waveform, is correlated with blood rheology andVn is calculated by dividing the maximum blood flow velocity Vx by theintegrated value of the pulse velocity waveform. That is, Vn iscalculated by following Equation 1. As mentioned above, Equation 1 isexpressed as Vn=C×Vx/(integrated value of pulse velocity waveform).

Incidentally, in the case in which the blood rheology measuring methodof the embodiment is applied to a person having blood rheology in whichthe total blood pass time period calculated by using the micro-channelarray according to the conventional method is 60 sec to therebycalculate the pulse velocity waveform and the correction coefficient Cis calculated such that Vn of Equation 1 becomes 60, when the total passtime period of the same person is changed to 35 sec, when Vn iscalculated from Equation 1 by using C calculated above, there is shown avalue of 35 with an error of ±8%. Either of V1 and Vn can be found to becorrelated with blood rheology and therefore, the analysis may becarried out by either of the methods.

(Embodiment 2)

According to Embodiment 2 of the invention, there is provided bodytemperature compensating means to above Embodiment 1. A mode of puttingthe blood rheology measuring apparatus on the finger is similar to thatof FIG. 6. Further, FIG. 9 shows a perspective sectional view of thefinger ring portion 1 viewing from the B direction of FIG. 6B. The bloodrheology measuring apparatus of Embodiment 2 is constituted by beingclassified in two of the finger ring portion 1 and the signal processingportion 2 similar to Embodiment 1 and as shown by FIG. 9, there arepresent the ultrasonic wave sensor portion 3 and a temperature sensor 7on the inner side of the finger ring portion 1. Further, also thetemperature sensor 7 is attached to the portion of the finger 6 shiftedto the left of the center of the belly in order to measure temperatureat a vicinity of the artery 5 similar to the ultrasonic sensor portion.Thereby, reflection from the artery can firmly be caught and accuracy ofmeasuring blood flow is promoted. Although according to Embodiment 2,the portions are attached to shift to the left, even when the portionsare attached to shift to the right to aim at the artery on the rightside, the effect stays the same.

The blood rheology measuring apparatus of Embodiment 2 is normallyportable by mounting the finger ring portion 1 to the finger 6 andmounting the signal processing portion 2 to the arm. Further, also thesignal processing portion 2 may be mounted to the finger 6 similar tothe finger ring portion 1. The signal processing portion 2 and theultrasonic wave incident portion 31, the ultrasonic wave detectingportion 32 and the temperature sensor portion 7, are connected by leadwires. The driving voltage signal is inputted from the signal processingportion 2 to the ultrasonic wave incident portion 31 via the lead wireand at the ultrasonic wave detecting portion 32, the measured voltagesignal is inputted to the signal processing portion 2. Further, atemperature signal of the temperature sensor 7 is outputted to thesignal processing portion 2 via the lead wire.

FIG. 10 shows a block diagram showing an inner constitution of thesignal processing portion 2 of the blood rheology measuring apparatus ofEmbodiment 2 and a state of connecting the signal processing portion 2,the ultrasonic wave sensor portion 3 and the temperature sensor 7 atinside of the finger ring portion 1. As illustrated, the signalprocessing portion 2 is generally constituted by the drive portion 21,the receive portion 22, the signal operating portion 23, the outputportion 24 and a temperature receiving portion 25. A difference betweenEmbodiment 1 and Embodiment 2 resides in that the temperature sensor 7and the temperature receiving portion 25 are further installed andtemperature compensating operation is carried out in the operationalprocessing at the signal operating portion 23 and according to theembodiment, when the blood flow velocity is calculated, the blood flowvelocity is corrected by using temperature at a vicinity of the artery 5of the finger portion 6 received by the temperature receiving portion25. The artery 5 of the finger portion 6 is sensitive to a change intemperature, the artery is contracted at low temperature, the blood flowvelocity is reduced and therefore, by compensating for an amount of achange in the blood flow caused by expansion or contraction of the bloodvessel based on body temperature information by the temperature sensor,information in correspondence with blood flow rheology can accurately beprovided.

When temperature is measured in calculating blood flow velocity andcalculating to correct the blood flow velocity by the temperature tothereby determine the correction coefficient C by using a pulse velocitywaveform calculated thereby as shown in Embodiment 2, in the calculationfor calculating Vn, blood rheology can be calculated with an error of±5%. Promotion of accuracy of 3% can be confirmed in comparison with theerror of ±8% in Embodiment 1 in which temperature compensation is notcarried out. Further, generally, the blood vessel is contracted in astate of low temperature and flow of blood to a distal end is extremelydeteriorated. When the blood vessel is conversely warmed, a constantcirculating state is constituted. It seems that influence of thetemperature is difficult to be effected when the blood vessel is warmedup to about the body temperature (36° C.). Therefore, when the bloodvessel at a periphery of a measured portion is expanded by providing aheat generating body at a vicinity of the measured portion, the changein blood flow can accurately be measured with excellent reproducibilityand accordingly, information with regard to blood rheology canaccurately be assessed.

As a heat generating body, a heater or the like can also be used andwhen a piezoelectric element of PZT or the like is used for transmittingan ultra sonic wave as a measuring portion, the piezoelectric elementper se generates heat and therefore, the piezoelectric element can alsobe utilized.

Further, in order to accurately measure temperature, or effectivelytransmit heat of a heat generating body, it is preferable that thefinger ring portion 1 is made of a material which is difficult totransmit heat and ceramics or the like is pertinent therefor. Further,generally, when the pulse number is increased, the blood flow velocityis also increased and therefore, when the pulse number is increased tobe larger than that at normal occasion, by measuring the pulse numberand carrying out a correction by the pulse number (for example, dividingthe blood flow velocity by the pulse number or the like), themeasurement accuracy can further be promoted. The pulse number can bemeasured by measuring a temporal interval of peaks of the blood flowvelocity in FIG. 1 for respective pulse and constituting a numberinverse thereto.

(Embodiment 3)

FIG. 11 is a view showing an outlook constitution of a blood rheologymeasuring apparatus according to a third embodiment of the invention.Although the embodiment is similar to above Embodiment 1 in that theembodiment is constituted by the first blood rheology analyzing methodaccording to the invention of calculating blood rheology by dividing themaximum blood flow velocity Vx shown in FIG. 1 by the integrated valueof the pulse velocity waveform (the integrated value of the pulsevelocity waveform in one period of pulse), the embodiment differs fromEmbodiment 1 in that a position of measuring blood flow is basicallydisposed at a finger tip portion frontward from the first joint of thefinger. As shown by FIG. 11, the blood rheology measuring apparatus isconstructed by a constitution including the signal processing portion 2in a mouse type blood rheology measuring apparatus 11.

FIG. 12 illustrates a section taken along a line A–A′ of FIG. 11. Asshown by FIG. 12, the ultrasonic wave sensor portion 3 is present on anupper side of the mouse type blood rheology measuring apparatus 11. Theultrasonic wave sensor portion 3 is attached with the ultrasonic waveincident portion 31 and the ultrasonic wave detecting portion 32 to bebrought into contact with the belly portion of the fingertip 61.Further, the artery 5 present in the finger tip 61 passes the bellyportion of the finger tip 61 and therefore, in order to measure flow ofblood of the artery 5, the ultrasonic wave incident portion 31 and theultrasonic wave detecting portion 32 are attached to the central portionof the belly of the finger tip 61 as shown by FIG. 12 such that anultrasonic wave can be made accurately incident to aim at the artery 5(including the capillary artery).

Further, FIG. 13 illustrates a section taken along a line B–B′ of FIG.11. As shown by FIG. 13, the apparatus is recessed such that the centralportion of the belly of the finger tip 61 is disposed at the ultrasonicwave sensor portion 3. Thereby, reflection from the artery 5 can firmlybe caught and accuracy of measuring blood flow is promoted. Althoughaccording to Embodiment 3, the mode of the apparatus is constituted bythe mouse type, the mode is not limited thereto but the blood rheologymeasuring apparatus can be constituted by installing the sensor at theposition brought into contact with the finger tip as in Embodiment 3 sofar as the apparatus can be gripped by the finger.

The blood rheology measuring apparatus of Embodiment 3 is portable sincethe signal processing portion 2 is included in the mouse type bloodrheology measuring apparatus 11. The signal processing portion 2 and theultrasonic wave incident portion 31 and the ultrasonic detecting portion32 installed at the mouse type blood rheology measuring apparatus 11 areconnected by lead wires, the driving voltage signal is inputted from thesignal processing portion 2 to the ultrasonic incident portion 31 viathe lead wire and at the ultrasonic wave detecting portion 32, themeasured voltage signal is inputted to the signal processing portion 2.

A block diagram showing the inner constitution of the signal processingportion 2 of the blood rheology measuring apparatus of Embodiment 3 andthe state of connecting the signal processing portion 2 and theultrasonic wave sensor portion 3 at inside of the mouse type bloodrheology measuring apparatus 11, is basically the same as FIG. 8 ofEmbodiment 1. As illustrated, the signal processing portion 2 isgenerally constituted by the drive portions 21, the receive portion 22,the signal operating portion 23 and the output portion 24. The driveportion 21 of Embodiment 3 oscillates PZT installed at the ultrasonicwave incident portion 31 and transmits drive voltage for making anultrasonic wave incident on the artery 5. The receive portion 22receives voltage generated when PZT installed at the ultrasonic wavedetecting portion 32 receives the ultrasonic wave. The signal operatingportion 23 carries out various processings with regard to measurement ofblood rheology by executing processing programs stored to a storageregion (illustration is omitted) provided at inside thereof and outputsa result of the processings to the output portion 24.

Further, the signal operating portion 23 calculates the Doppler effectof blood flow by comparing the frequency of the ultrasonic wave emittedfrom the ultrasonic wave incident portion 31 and the frequency of theultrasonic wave received by the ultrasonic wave detecting portion 32.Further, the signal operating portion 23 calculates the velocity ofblood flow flowing in the artery 5 by a change in the frequency andcalculates the temporal change of the velocity. Further, the form of thetemporal change of the blood flow velocity appearing in pulsing, iscorrelated with rheology of blood and blood rheology is calculated froma change in the blood flow velocity appearing in pulsing.

Also according to the blood rheology measuring method of the embodiment,blood rheology is calculated by following Equation 1. The ratio Vn ofthe maximum blood flow velocity Vx as compared with the pulse velocitywaveform, is correlated with blood rheology and Vn is calculated bydividing the maximum blood flow velocity Vx by the integrated value ofthe pulse velocity waveform. As described above, Equation 1 is expressedas Vn=C×Vx/(integrated value of pulse velocity waveform). Incidentally,when the correction coefficient C is calculated such that Vn of Equation1 becomes 60 by calculating the pulse velocity waveform by applying theblood rheology measuring method of the embodiment to a person havingblood rheology in which the total pass time period calculated by usingthe micro-channel array of the conventional method, is 60 sec, in thecase in which the total blood pass time period of the same person ischanged to 35 sec, when Vn is calculated from Equation 1 by using Ccalculated above, a value of 35 is shown with an error of ±8%.

Further, a constant correlation is confirmed even with V1=C×Vx andtherefore, the analysis can be carried out by either of the methods.

(Embodiment 4)

FIG. 14 is a view showing a sectional view of the mouse type bloodrheology measuring apparatus 11 according to a fourth embodiment of theinvention. Although the blood rheology measuring apparatus of Embodiment4 is constructed by a constitution including the signal processingportion 2 in the mouse type blood rheology measuring apparatus 11similar to Embodiment 3, as shown by FIG. 14, the ultrasonic sensorportion 3 and the temperature sensor 7 are installed on the inner sideof the mouse type blood rheology measuring apparatus 11 to therebyprovide body temperature compensating means. Further, similar toEmbodiment 3, the ultrasonic wave sensor portion 3 is attached with theultrasonic wave incident portion 31 and the ultrasonic wave detectingportion 32 to be brought into contact with the belly portion of thefinger tip 61. Further, the artery 5 disposed in the finger tip 61passes the belly portion of the finger tip 61 and therefore, in order tomeasure flow of blood of the artery, the ultrasonic wave incidentportion 31 and the ultrasonic wave detecting portion 32 are attached tothe central portion of the belly of the finger tip 61 as shown by FIG.14 such that an ultrasonic wave can be incident accurately to aim at theartery 5. Further, also the temperature sensor 7 is attached to thecentral portion of the belly of the finger tip 61 similar to theultrasonic wave sensor portion 3 in order to measure temperature at avicinity of the artery 5. Thereby, reflection of the artery 5 can firmlybe caught and accuracy of measuring blood flow is promoted.

The temperature sensor portion 7 is connected to the signal processingportion 2 by the lead wire similar to the ultrasonic wave incidentportion 31 and the ultrasonic wave detecting portion 32 installed at themouse type blood rheology measuring apparatus 11. The temperature signalof the temperature sensor 7 is outputted to the signal processingportion 2 via the lead wire.

A block diagram showing the inner constitution of the signal processingportion 2 of the blood rheology measuring apparatus of Embodiment 4 andthe state of connecting the signal processing portion 2 and theultrasonic sensor portion 3 at inside of the mouse type blood rheologymeasuring apparatus 11, is basically the same as FIG. 10 of Embodiment2. As illustrated, the signal processing portion 2 is generallyconstituted by the drive portion 21, the receive portion 22, the signaloperating portion 23 and the output portion 24. A difference betweenEmbodiment 3 and Embodiment 4 resides in that the temperature sensor 7and the temperature receiving portion 25 are further installed and thetemperature compensating operation is carried out by the operationalprocessing at the signal operating portion 23 and according to theembodiment, in calculating the blood flow velocity, the blood flowvelocity is corrected by using the temperature at a vicinity of theartery 5 of the finger portion 6 received by the temperature receivingportion 25. The artery 5 of the finger portion 6 is sensitive to achange in temperature, when temperature becomes low, the artery iscontracted, the blood flow velocity is reduced and therefore, bycompensating for an amount of the change in the blood flow caused byexpansion or contraction of the blood vessel based on the bodytemperature information by the temperature sensor, information incorrespondence with blood rheology can accurately be provided similar toEmbodiment 2.

In calculating the blood flow velocity by Embodiment 4, when thetemperature is measured and the blood flow velocity is calculated bycorrecting the blood flow velocity by the temperature to therebydetermine the correction coefficient C by using the pulse velocitywaveform calculated thereby, in the calculation of calculating Vn, bloodrheology can be calculated with an error of ±4%. Promotion of accuracyof 4% can be confirmed in comparison with the error of ±8% in Embodiment3 in which temperature compensation is not carried out.

(Embodiment 5)

FIG. 15A is an outlook view of a wrist watch type blood rheologymeasuring apparatus 12 according to a fifth embodiment of the inventionand FIG. 15B is a view showing a measuring state of the wrist watch typeblood rheology measuring apparatus 12. FIG. 16 illustrates a sectiontaken along a line A–A′ of FIG. 15B.

The blood rheology measuring apparatus of Embodiment 5 is constructed bya constitution including the signal processing portion 2 (notillustrated) in the wrist watch type blood rheology measuring apparatus12. Further, as shown by FIG. 16, there are present the ultrasonic wavesensor portion 3 and the temperature sensor 7 on an inner side of awrist watch. Further, similar to Embodiment 4, the ultrasonic wavesensor portion 3 is attached with the ultrasonic wave incident portion31 and the ultrasonic wave detecting portion 32 to be brought intocontact with the portion of the belly of the finger tip 61. Further, theartery 5 disposed in the finger tip 61 passes the belly portion of thefinger tip 5 and therefore, in order to measure flow of blood of theartery 5, the ultrasonic wave incident portion 31 and the ultrasonicwave detecting portion 32 are attached to be brought into contact withthe central portion of the belly of the finger tip 61 such that anultrasonic wave can accurately be incident to aim at the artery 5.Further, also the temperature sensor 7 is attached to the centralportion of the belly of the finger tip 61 similar to the ultrasonicsensor portion 3 to measure temperature at a vicinity of the artery 5.Thereby, reflection from the artery 5 can firmly be caught and accuracyof measuring blood flow is promoted.

As shown by FIG. 16, the temperature sensor 7 is disposed not on theside of the finger tip of the ultrasonic sensor portion 3 but on thepalm side. The reason is that when the temperature sensor 7 is installedon the side of the finger tip of the ultrasonic wave sensor portion 3,the temperature sensor 3 is not brought into contact with the finger tipand accurate temperature cannot be measured.

The blood rheology measuring apparatus of Embodiment 5 is normallyportable since the signal processing portion 2 is included in the wristwatch type blood rheology measuring apparatus 12. The signal processingportion 2, and the ultrasonic wave incident portion 31, the ultrasonicwave detecting portion 32 and the temperature sensor portion 7 installedin the wrist watch type blood rheology measuring apparatus 12, areconnected by lead wires. The driving voltage signal is inputted from thesignal processing portion 2 to the ultrasonic wave incident portion 31via the lead wire and at the ultrasonic wave detecting portion 32, themeasured voltage signal is inputted to the signal processing portion 2.Further, the temperature signal of the temperature sensor 7 is outputtedto the signal processing portion 2 via the lead wire. The output can beoutputted to a display screen of the wrist watch.

A block diagram showing the inner constitution of the signal processingportion of the wrist watch type blood rheology measuring apparatus 12 ofEmbodiment 5 and the state of connecting the signal processing portion2, the ultrasonic wave sensor portion 3 and the temperature sensor 7 atinside of the wrist watch type blood rheology measuring apparatus 12, isbasically the same as FIG. 10. As illustrated, the signal processingportion 2 is generally constituted by the drive portion 21, the receiveportion 22, the signal operating portion 23, the output portion 24 andthe temperature receiving portion 25.

The blood rheology measuring method of the embodiment is calculated byfollowing Equation 1 and the temperature compensation is carried outbased on the body temperature detected value similar to Embodiment 2 andEmbodiment 4.

(Embodiment 6)

FIG. 17 illustrates a constitution view of an outlook of a finger sacktype blood rheology measuring apparatus 13 of a blood rheology measuringapparatus according to a sixth embodiment of the invention and FIG. 18illustrates a section taken along a line A–A′ of FIG. 17. The bloodrheology measuring apparatus of Embodiment 6 is constituted by beingclassified into the finger sack type blood rheology measuring apparatus13 and the signal processing portion 2. As shown in FIG. 18, there arepresent the ultrasonic wave sensor portion 3 and the temperature sensor7 on an inner side of the finger sack type blood rheology measuringapparatus 13.

Similar to Embodiment 4, the ultrasonic wave sensor portion 3 isattached with the ultrasonic wave incident portion 31 and the ultrasonicwave detecting portion 32 to be brought into contact with the portion ofthe belly of the finger tip 61. Further, the artery 5 disposed in thefinger tip 61 passes the belly portion of the finger tip 61 andtherefore, in order to measure flow of blood of the artery, theultrasonic wave incident portion 31 and the ultrasonic wave detectingportion 32 are attached to be brought into contact with the centralportion of the belly of the finger tip 61 such that an ultrasonic wavecan accurately be incident to aim at the artery 5.

Further, also the temperature sensor 7 is attached to the centralportion of the belly of the finger tip 61 similar to the ultrasonic wavesensor portion 3 in order to measure temperature at a vicinity of theartery. Thereby, reflection from the artery 5 can firmly be caught andaccuracy of measuring blood flow is promoted.

The blood rheology measuring apparatus of Embodiment 6 can normally becarried and can carry out measurement normally by mounting the fingersack type blood rheology measuring apparatus 13 to the finger tip andcarrying the signal processing portion 2 (not illustrated) on the arm.Further, the signal processing portion 2 can also be included in thefinger sack type blood rheology measuring apparatus 13.

The signal processing portion 2 and the ultrasonic wave incident portion31, the ultrasonic wave detecting portion 32 and the temperature sensorportion 7 installed at the finger sack type blood rheology measuringapparatus 13, are connected by lead wires. The driving voltage signal isinputted from the signal processing portion 2 to the ultrasonic waveincident portion 31 via the lead wire and at the ultrasonic wavedetecting portion 32, the measured voltage signal is inputted to thesignal processing portion 2. Further, the temperature signal of thetemperature sensor 7 is outputted to the signal processing portion 2 viathe lead wire.

A block diagram showing the inner constitution of the signal processingportion 2 of the finger sack type blood rheology measuring apparatus 13of Embodiment 6 and the state of connecting the signal processingportion 2, the ultrasonic wave sensor portion 3 and the temperaturesensor 7 at inside of the wrist watch type blood rheology measuringapparatus 12, is basically similar to FIG. 10.

The blood rheology measuring method of the embodiment is calculated byfollowing Equation 1 and the temperature compensation is carried outbased on the body temperature detected value similar to Embodiment 2,Embodiment 4 and Embodiment 5.

Further, also according to the finger sack type blood rheology measuringapparatus explained in the embodiment, by providing a cuff structure,mentioned later, as in FIG. 25, a change in blood flow velocity by achange in blood pressure and accordingly, a change in blood rheology canbe corrected.

(Embodiment 7)

An explanation will be given of Embodiment 7 through Embodiment 10 asfollows and with regard to these embodiments, measurement data of fivesubjects is sampled and an investigation is carried out on a comparisonthereof. Before explaining the respective embodiments, there is shownbasic data of measuring highest blood pressure, lowest blood pressureand a measured total blood pass time period value before meal and aftermeal with respect to the five subjects in Table 1.

TABLE 1 Highest blood Lowest blood micro-channel Subject Conditionpressure pressure (sec) A before meal 115.0 63.5 56.3 after meal 110.563.5 52.7 B before meal 109.0 75.0 43.1 after meal 100.0 62.5 41.2 Cbefore meal 119.0 89.0 48.7 after meal 106.5 79.0 44.1 D before meal194.0 133.0 54.1 after meal 175.0 122.0 52.3 E before meal 109.5 77.052.5 after meal 110.0 71.5 44.0

Next, an explanation will be given of a blood rheology measuringapparatus according to a seventh embodiment of the invention. Accordingto the embodiment, there is used a finger ring type sensor as shown byFIG. 6 and FIG. 7 as a blood flow velocity detecting portion and thereis adopted the second method, that is, a method of sampling a maximumfrequency from a frequency waveform as a method of analyzing bloodrheology. By using Embodiment 7, the five subjects are measured andthere are provided a maximum frequency indicating blood rheology and avalue produced by dividing the maximum frequency by a highest bloodpressure value. The data is shown in Table 2.

TABLE 2 Maximum frequency/ Subject Condition Maximum frequency Highestblood pressure A before meal  914 7.9 after meal  703 6.4 B before meal1669 15.3 after meal 1918 19.2 C before meal 1014 8.5 after meal 168815.9 D before meal 1100 5.7 after meal 1856 10.6 E before meal 1177 10.7after meal 1315 12.0

FIGS. 19A and 19B show the data indicated by graphs in which FIG. 19Ashows a correspondence between the maximum frequency and themicro-channel and FIG. 19B shows a correspondence between the valueproduced by dividing the maximum frequency by the highest blood pressurevalue and the micro-channel. When a result thereof is observed, it isknown from the graph of FIG. 19A that a correlation is establishedwithout taking an individual difference into consideration except dataof subject D having a high blood pressure value in the data adoptingdata of the second method of analyzing blood rheology based on theartery blood flow information at the finger position (by providing afrequency histogram from Doppler shift intensity information, furtherproviding a frequency waveform and providing a maximum frequencythereof). The correlation can be grasped not as a linear relationshipbut as a relationship of a quadratic curve as indicated by a brokenline. There is an enormous significance in that although in the case ofdata of the first method of analyzing blood rheology, it is necessary tosample blood and calculate the correction value C of an individual bymeasurement by the micro-channel array, according to the embodiment, thedata can directly be measured. Further, it is known from the graph ofFIG. 19B that there is established a correlation with regard to dataproduced by dividing data of the second method of analyzing bloodrheology based on the artery blood flow information at the fingerposition by a blood pressure value without taking an individualdifference into consideration including data of subject D having a highblood pressure value. The correlation can be grasped not as a linearrelationship but as a relationship of a quadratic curve as shown by abroken line. It is found that the embodiment excellently corrects anamount of variation by blood pressure and can be regarded as acompensation method particularly effective for subjects having highblood pressure and low blood pressure.

(Embodiment 8)

In the case of a blood rheology measuring apparatus according to aneighth embodiment of the invention, there is detected blood flowvelocity of the artery of the finger tip by using a mouse type sensor asshown by FIG. 11 through FIG. 13 as a blood flow velocity detectingportion and as a method of analyzing blood rheology, the second method,that is, a method of sampling the maximum frequency from the frequencywaveform is adopted. By using Embodiment 8, five subjects are measuredand there are provided the maximum frequency indicating blood rheologyand the value produced by dividing the maximum frequency by the highestblood pressure value. The data is shown in Table 3.

TABLE 3 Maximum frequency/ Subject Condition Maximum frequency Highestblood pressure A before meal  904 7.9 after meal 1315 11.9 B before meal2024 18.6 after meal 2557 25.6 C before meal 1846 15.5 after meal 206219.4 D before meal 2880 14.8 after meal 2139 12.2 E before meal 204718.7 after meal 1764 16.0

FIGS. 20A and 20B indicate the data by graphs in which FIG. 20A shows acorrespondence between the maximum frequency and the micro-channel andFIG. 20B shows a correspondence between the value of the maximumfrequency divided by the highest blood pressure value and themicro-channel. When a result there of is observed, it is known from thegraph of FIG. 20A that a correlation is established without taking anindividual difference into consideration except data of subject D havinga high blood pressure value in the data adopting data by the secondmethod of analyzing the rheology based on the artery blood flowinformation at the finger tip position. The correlation can be graspedas a linear relationship according to the embodiment. According to theembodiment, the relationship can directly be measured with no need ofcalculating the correction value C similar to Embodiment 7. Further, itis known from the graph of FIG. 20B that a correlation is establishedwithout taking an individual difference into consideration includingdata of subject D having a high blood pressure value in the dataadopting data of the second method of analyzing blood rheology based onthe artery blood flow information at the finger tip position. Thecorrelation can be grasped as the linear relationship as shown by abroken line. According to the embodiment, it is found that an amount ofvariation by blood pressure is well compensated for and also in theembodiment, the processing of dividing the maximum frequency by theblood pressure value is a compensation method effective for subjectshaving high blood pressure and low blood pressure.

(Embodiment 9)

In the case of the blood rheology measuring apparatus according to aninth embodiment of the invention, there is used a finger ring typesensor as shown by FIG. 6 and FIG. 7 as a blood flow velocity detectingportion and there is adopted a third method, that is, a method ofsampling an area of one pulse from the frequency waveform as a method ofanalyzing blood rheology. Five subjects are measured by using Embodiment9 and there are provided the area of one pulse indicating blood rheologyand the value produced by dividing the area by the height blood pressurevalue. The data is shown in Table 4.

TABLE 4 Subject Condition Area Area/Highest blood pressure A before meal404 3.5 after meal 334 3 B before meal 1101  10.1 after meal 1269  12.7C before meal 540 4.5 after meal 1048  9.8 D before meal 547 2.8 aftermeal 1104  6.3 E before meal 676 6.2 after meal 925 8.4

FIGS. 21A and 21B indicate the data by graphs in which FIG. 21A shows acorrespondence between the area of one pulse and the micro-channel andFIG. 21B shows a correspondence between a value of the area of one pulsedivided by the highest blood pressure and the micro-channel. When aresult thereof is observed, it is known from graph A that a correlationis established without taking an individual difference intoconsideration except data of subject D having a high blood pressurevalue in the data adopting the data of the third method of analyzingblood rheology based on the artery blood flow information at the fingerposition (by providing a frequency histogram from Doppler shiftintensity information, further providing the frequency waveform andproviding the area of one pulse). The correlation can be grasped as alinear relationship as shown by a broken line. According to theembodiment, it is known that the relationship can directly be measuredwith no need of calculating the correction value C of an individual.Further, it is known from the graph of FIG. 21B that a correlation isestablished without taking an individual difference into considerationincluding data of subject D having the high blood pressure value in thedata produced by dividing data of the third method of analyzing bloodrheology based on the artery blood flow information at the fingerposition by the blood pressure value. The correlation can be graspedalso as a linear relationship. According to the embodiment, it is foundthat an amount of variation by blood pressure is well compensated forand the embodiment can be regarded as a compensation method particularlyeffective for subjects having high blood pressure and low bloodpressure.

(Embodiment 10)

FIG. 22 is an explanatory view of flattening a portion of the fingerring portion 1 brought into contact with the berry portion of the finger6 and providing an elastic body 90 of silicone rubber or the like at agap between the finger 6 and the finger ring portion 1. A position ofthe artery 5 of the finger tip is disposed at a position at which anangle θ in FIG. 22 falls in a range of about 10 degrees through 80degrees and when the finger ring portion 1 is constituted by acompletely cylindrical shape, positioning of a measuring portion 101becomes difficult. Therefore, by constituting the shape as shown by FIG.22, specifying a portion in contact with the belly portion of the finger6 and arranging a measuring portion 101 with the belly portion as areference, the measuring portion 101 can precisely be positioned to avicinity of the artery 5 and reproducibility and reliability ofmeasurement can be promoted.

Further, it is preferable to produce a state in which a space isdifficult to produce between the finger 6 and the finger ring portion 1and the measuring portion 101 and the temperature sensor 7 are broughtinto close contact with the skin of the finger 6 and do not touch withoutside air in using the apparatus.

Therefore, there may be constructed a constitution in which the fingerring portion 1 is fastened by the elastic body 90 of silicone rubber orthe like under constant pressure or a seat of silicone rubber or thelike is pasted on an inner periphery of the finger ring portion 1 to bebrought into close contact with the skin.

FIG. 23 is a perspective view viewing the finger ring portion 1 of FIG.22 from D direction when the elastic body 90 is provided at otherposition and the temperature sensor 7 is provided. The elastic body 90is provided to sandwich the measuring portion 101 and the temperaturesensor 7, by attaching the finger ring portion 1 to the finger 6, thetemperature sensor 7 is prevented from touching the outside air and ismade to be difficult to be effected with influence of outside air andaccordingly, accuracy of assessing blood rheology can be promoted.

As a material of the elastic body 90, since the elastic body 90 is usedby being brought into contact with the living body, in consideration ofrash or the like of the skin, silicone rubber having excellentadaptability with the living body is suitable.

(Embodiment 11)

FIG. 24 is an explanatory view showing a constitution of providing aninput portion 50 to the blood rheology measuring apparatus according toEmbodiment 4. Generally, the blood flow velocity of the finger tipdiffers by gender and a blood pressure value, even in the case of thesame rheology (total blood pass time period), there is a tendency that afemale subject is slower than a male subject and the higher the bloodpressure, the faster than blood flow velocity. By correcting thedifference by gender and blood pressure, the above-described correlationbetween the blood flow velocity and blood rheology is improved andreliability of the blood rheology measuring apparatus of the inventionis promoted.

By inputting gender and a blood pressure value by the input portion 50,blood rheology can be measured further accurately by using an optimumcorrection coefficient. Further, eating habit information of a subject(eating when and what, or the like) can be inputted by the input portion50 and it can be determined whether eating habit and daily life of asubject is suitable for the subject in combination with information withregard to provided blood rheology (for example, by measuring bloodrheology before meal and after meal). Further, the input portion may notbe of a timepiece type but information can be inputted also bycommunication from an apparatus having an input portion such as aportable telephone or the like.

(Embodiment 12)

FIG. 25 is an explanatory view of a constitution providing the measuringportion 101 at an inner periphery of a cuff 80 mountable to the fingerin place of the finger ring portion 1 of the blood rheology measuringapparatus according to Embodiment 2.

The cuff 80 is constituted by a shape of an expandable and contractablebag, comprising an inner periphery 81 and an outer periphery 82 andhaving an air layer 60. The air layer 60 is connected with a tube 71 andpredetermined pressure can be applied from a pressure applying portion,not illustrated, to the air layer 60.

Generally, according to a noninvasive blood pressure meter, the arteryis pressurized by a cuff, pressure in starting to flow blood flow(Korotkoff's sound starts to be heard) is defined as the highest bloodpressure and pressure in starting to flow constant blood flow(Korotokoff's sound is extinguished) is defined as the lowest bloodpressure. By measuring blood flow velocity by the measuring portion 101,the highest and the lowest blood pressures are measured and also a valueof blood rheology is measured.

By measuring and assessing blood rheology simultaneously with measuringblood pressure, also pressure at that occasion can accurately be graspedand simultaneously with measuring blood pressure, an error of bloodrheology by an individual difference of blood pressure can be correctedfurther accurately.

Although according to the embodiment, blood rheology is measuredsimultaneously with measuring blood pressure by the blood pressuremeter, the apparatus can also be used as a pulse meter by measuring atemporal interval between peaks of the waveform of FIG. 1. Further, itis also possible to arrange the cuff at the finger tip and utilizingblood pressure at a vicinity of the capillary at the finger tip.

(Embodiment 13)

FIG. 26 is an explanatory view showing a constitution providing themeasuring portion at the finger tip (not illustrated) in the bloodrheology measuring apparatus according to Embodiment 4. When a state ofhigh blood rheology (high viscosity) is chronically continued, there isa high possibility of falling into an extremely dangerous health statesuch as arterial sclerosis.

Therefore, blood rheology is always measured and when the state of highblood rheology (high viscosity) is maintained or when blood rheologybecomes equal to or lower than a predetermined value, by alarming a userby a detecting portion 85 of LED or the like, displaying to urge tosupply water, improvement of life (insufficient sleep or the like) atadisplay portion 84, the above-described state can be avoided.

(Embodiment 14)

FIG. 27 is an explanatory view showing a constitution providing themeasuring portion at the finger tip (not illustrated) in the bloodrheology measuring apparatus according to Embodiment 4. FIG. 27 is anexplanatory view showing a state of displaying a daily trend of bloodrheology at a display portion 84. The blood rheology is changed by dailylife such as sleep time period, eating habit, presence or absence ofexercise or the like and by observing a change in the blood rheology, itcan be determined whether life of the subject is healthy, which canamount to prevention of disease of the circulatory system such asarterial sclerosis.

Blood rheology is changed daily and it is difficult to determine thehealth state of the subject by only measuring blood rheology once.Therefore, for example, when blood rheology before meal and bloodrheology after meal are measured for a week, the health state of thesubject can be grasped further accurately. Further, there can also beconfirmed an effect in the case of continuously intaking food forimproving blood rheology, for example, fermented soybeans, blackvinegar, tomato juice, vegetable juice or the like.

FIG. 28 is an explanatory view showing a behavior of transmitting ameasured value of blood rheology to a terminal by way of wireless,determining the health state of the subject based on the data andtransferring a result of diagnosis. In FIG. 28, a terminal at adestination of transfer is omitted. Numeral 86 designates an antenna.Since a change in a value of blood rheology is small or the value ischanged by measuring time or physical condition and therefore, bytransferring measured data to the terminal, diagnosing the data by aspecialist such as medical doctor and returning advice with regard tolife to the user (advice with regard to food for improving bloodrheology, advice with regard to sleep time or exercise time) a concernof erroneously recognizing the health state can be avoided and a stateof blood rheology of the subject can be assessed and accordingly, thehealth state of the subject can be assessed and diagnosed furtheraccurately.

The blood rheology measuring apparatus according to the inventioncomprises means for detecting the flow velocity of the blood flowing inthe blood vessel in the mode of the Doppler shift signal by transmittingand receiving the wave from the face of the skin and means for analyzingblood rheology from the temporal change of the flow velocity value ofthe blood detected by the means and therefore, small-sized formation ofthe apparatus can be realized and since the measurement is carried outnoninvasively, blood rheology can be measured simply at any time atanywhere even at outside of a medical institution without applyingburden on a subject.

Further, according to the blood rheology measuring apparatus of theinvention for analyzing blood rheology from the temporal change of theflow velocity value of the blood by dividing the maximum blood flowvelocity of one pulse by the integrated value of the pulse velocity,although the measured blood flow velocity is not dependent only on bloodrheology but dependent on a condition of thickness of the blood vessel,the wall quality or the blood pressure, when the correction amount incorrespondence with the absolute value is provided by carrying out thecorrection by measurements by the conventional method capable ofcarrying out absolute measurement by comparing with the reference ofphysiological salt water or the like and the method of the invention inparallel, blood rheology can absolutely be measured by the apparatus.

According to the blood rheology measuring apparatus comprising means fordetecting a flow velocity of the blood flowing in the blood vessel in amode of a Doppler shift signal by transmitting and receiving a wave froma face of the skin, means for calculating an intensity of each offrequency components of the Doppler shift signal (histogram), means forextracting a maximum frequency in a signal of an intensity level equalto or larger than a threshold in the histogram, or a maximum frequencywhen an integrated value from a low frequency component reaches apredetermined rate of a total thereof in the histogram and means forproviding a temporal change waveform of the extracted frequency(frequency waveform) and the blood rheology measuring apparatus of theinvention, wherein a blood rheology is analyzed by an area value of aportion at and above a line connecting a minimum value of one pulsewaveform and a minimum value of a successive pulse waveform of thefrequency waveform, small-sized formation of the apparatus can berealized, since the measurement can be carried out noninvasively, bloodrheology can be measured simply at any time at anywhere even at outsideof a medical institution without applying burden on a subject andfurther, it is not necessary to provide the correction amount incorrespondence with the absolute value by carrying out the correction ofthe measurements of the conventional method and the method of theinvention in parallel and blood rheology can directly be measuredabsolutely by the apparatus.

According to the blood rheology measuring apparatus of the inventionadopting an ultrasonic wave transmitter and receiver for transmittingand receiving an ultrasonic wave to and from the artery at the fingertip portion as means for detecting the flow velocity of the bloodflowing in the blood vessel or an ultrasonic wave transmitter andreceiver for transmitting and receiving an ultrasonic wave to and fromthe artery of the finger portion, since the measured portion is thefinger, the blood flow velocity measuring portion can be downsized.

Further, according to the blood rheology measuring apparatus of theinvention, by providing means for detecting temperature of the bloodvessel portion and means for operating and compensating for an amount ofa change in the flow velocity of the blood based on expansion andcontraction of the blood vessel by a temperature value detected by themeans, blood rheology can be measured accurately.

Further, according to the blood rheology measuring apparatus of theinvention, by providing blood pressure measuring means and means foroperating and compensating for an amount of a change based on bloodpressure by dividing by a blood pressure value detected by the means,blood rheology can be measured accurately.

According to the invention, a structure of a holding portion isconstituted by a structure in which the finger ring is constituted by ashape capable of identifying an upper side and a lower side of a cutface when the finger ring is cut by a face orthogonal to an axialdirection thereof and the measuring portion is arranged at a position of10 degrees through 80 degrees when a vertical lower direction is definedas 0 degree centering on an axis of the cylinder. Thereby, an ultrasonicwave can be made to be incident to accurately aim at the artery and anaccuracy of measuring the flow velocity of the blood can be promoted andaccordingly, blood rheology can accurately be assessed.

Further, according to the invention, the blood rheology measuringapparatus is integrated with a sensor portion at an inner peripheralportion of the finger ring to be brought into contact with the fingerand the sensor portion is always carried along with the signalprocessing portion of the ultrasonic wave to be able to measure bloodrheology and therefore, a change in blood rheology in life of one daycan be assessed as continuous change, which can amount to prevention ofdisease of the circulatory system (myocardianl infarction or the like).

Further, according to the invention, by integrating the measuringportion in the blood rheology measuring apparatus to a cuff, not onlyblood rheology can be measured simultaneously with measuring bloodpressure but also by correcting blood rheology by a provided bloodpressure value, further accurate blood rheology information can beprovided which can amount to prevention of disease of the circulatorysystem.

1. A blood rheology measuring apparatus comprising: a measuring portionfor measuring blood circulation information inside of a living body fromoutside of the living body, the blood circulation information being amaximum blood flow velocity for one pulse; an information processingportion for processing the measured information from the measuringportion to obtain information concerning a blood rheology of the livingbody; and a data inputting portion for inputting individual informationof a person to be measured, the individual information being informationabout a food.
 2. A blood rheology measuring apparatus comprising: ameasuring portion for measuring blood circulation information inside ofa living body from outside of the living body, the blood circulationinformation being a maximum blood flow velocity for one pulse; and aninformation processing portion for processing the measured informationfrom the measuring portion to obtain information concerning a bloodrheology of the living body; wherein the measuring portion measures theinformation by a predetermined timing and when a predetermined value ofthe blood rheology is reached, the value is detected by the person to bemeasured.
 3. A blood rheology measuring apparatus comprising: ameasuring portion for measuring blood circulation information inside ofa living body from outside of the living body; and an informationprocessing portion for processing the measured information from themeasuring portion to obtain information concerning a blood rheology ofthe living body; wherein the blood circulation information is a maximumblood flow velocity for one pulse, and the blood rheology is analyzedfrom a temporal change of the blood flow velocity value by dividing amaximum blood flow velocity of one pulse by an integrated value of apulse velocity.
 4. A blood rheology measuring apparatus according toclaim 3; wherein the measuring portion and the information processingportion are integrally or individually made portable to thereby enablethe information concerning the blood rheology to be obtainedcontinuously or daily.
 5. A blood rheology measuring apparatus accordingto claim 3; wherein the blood circulation information is a blood flowvelocity based on a Doppler effect by a blood flow.
 6. A blood rheologymeasuring apparatus according to claim 3; wherein the measuring portioncomprises an ultrasonic wave sensor for transmitting and receiving anultrasonic wave.
 7. A rheology measuring apparatus according to claim 3;further comprising a data inputting portion for inputting individualinformation of a person to be measured.
 8. A blood rheology measuringapparatus according to claim 7; wherein the individual information isinformation about a food.
 9. A blood rheology measuring apparatusaccording to claim 3; wherein life habit information suitable for aperson to be measured is informed to a subject based on informationconcerning the blood rheology of the person to be measured.
 10. A bloodrheology measuring apparatus according to claim 3; further comprising adata holding portion for storing the information concerning the measuredblood rheology to enable a daily change in the blood rheology of theperson to be measured to be assessed from data stored to the dataholding portion.
 11. A blood rheology measuring apparatus according toclaim 3; further comprising a pressure measuring portion.
 12. A bloodrheology measuring apparatus according to claim 3; further comprising acuff; a mechanism for adjusting a pressure of fastening the cuff; and apressure measuring portion for measuring the pressure.
 13. A bloodrheology measuring apparatus according to claim 12; wherein theinformation concerning the blood rheology provided by the pressuremeasuring portion is operated and corrected.
 14. A blood rheologymeasuring apparatus according to claim 3; wherein a pulse number isderived from the information concerning the blood circulation providedby the measuring portion and the information concerning the bloodrheology is operated and corrected by the pulse number.
 15. A bloodrheology measuring apparatus according to claim 3; wherein the measuringportion measures the information by a predetermined timing and when apredetermined value of the blood rheology is reached, the value isdetected by the person to be measured.
 16. A blood rheology measuringapparatus according to claim 3; further comprising a temperaturemeasuring portion for measuring a temperature inside of the living bodyor a surface of the living body at a vicinity of the measuring portion.17. A blood rheology measuring apparatus according to claim 3; furthercomprising a temperature elevating portion for elevating the temperatureinside of the living body or the surface of the living body at thevicinity of the measuring portion.
 18. A blood rheology measuringapparatus according to claim 17; wherein the temperature elevatingportion is the same as the measuring portion.
 19. A blood rheologymeasuring apparatus according to claim 3; wherein the measuring portionis held by a structure capable of holding the measuring portion bybringing the measuring portion into contact with the surface of theliving body.
 20. A blood rheology measuring apparatus according to claim19; wherein the holding structure has a shape of a cylindrical fingerring, and the measuring portion is integrated to an inner peripheralportion of the finger ring to be brought into contact with the livingbody.
 21. A blood rheology measuring apparatus according to claim 20;wherein the measuring portion is integrated to the inner peripheralportion of the finger ring to be brought into contact with the livingbody by being shifted to either of a right side or a left side from aportion of the belly of the finger.
 22. A blood rheology measuringapparatus according to claim 20; wherein the temperature measuringportion is integrated to the inner peripheral portion of the finger ringto be brought into contact with the living body by being shifted toeither of a right side or a left side from a portion of the belly of thefinger.
 23. A blood rheology measuring apparatus according to claim 20;wherein the holding structure has a shape of a finger ring capable ofidentifying an upper side and a lower side of a cut face when the fingerring is cut by a face orthogonal to an axial direction thereof, and themeasuring portion is disposed at a position of 10 degrees through 80degrees when a lower direction of the cut face is defined as 0 degreecentering on an axis of the cylinder.
 24. A blood rheology measuringapparatus according to claim 19; wherein the holding structure is amember having an insulating property.
 25. A blood rheology measuringapparatus according to claim 19; wherein the holding structure is amember having an elasticity of a rubber.
 26. A blood rheology measuringapparatus according to claim 3; wherein the measuring portion measures achange in a blood flow velocity at a capillary of a finger tip.